Philip poore



products.

UNITED STATES PATENT- oFFIc PHILIP roonln, or

Lennon, ENGLAND.

DISTILLATIQN O F WOOD, WOODY FIBER, AND SIMILAR CABIBUNACEOUS SUBSTANCES.

-of which the following is a specification.

This invention relates to the destructive distillation of Wood, woody fiber and similar carbonaceous substances and has for its object to carry on the distillation under such conditions as to secure a high yield of acetic acid, wood naphtha, or other distillatio According to the invention I" admit steam at a temperature of from about 180 C. to

. about 270 G. into the -retort throughout the active e-riod of distillation or for a period extendmg over the time during which the exothermic reaction takes place and which generally commences on the charge reaching a temperature of about 270 (1., and I render the application of heat throughout the charge substantially'uniform. For this purpose the distillation may be efi'ected in re torts which are rotated continuously or periodically during the distillation as-idescribed in the specification filed pursuant to a copending application, the petition being dated the 20th January, 1919.

In carrying the invention into effect in the use of stationary cylindrical retorts into which the superheated steam is admitted at the bottom of the retort from a perforated pipe extending the length of the retort as described in the specification of the prior applidation made by me No. 239237 dated 10th June, 1918, I have'found that if the superheated steam on passing into the retort has a temperature of from 180 (J. to 27 0 C. a very high yield of acetic acid and other distillation products will be secured under the conditions there prevailing. In.

the distillation of pine wood and birch wood, I have found ifthe steam admitted to the retort has a temperature of from 210 'to 225 the highest yield of acetic acid and other distillation products will be secured. It will, however, be understood that in such a case the wood or other carbonaceous material is first cut up into pieces and dried so as to reduce its content of moisture to such an extent as conveniently practicable, for exampl'e to about five or ten per cent. of moisture Specification of Letters Patent.

Patented Nov. 15, 19 21. 1919. Serial No. 309,121.

and that the admission of superheated steaminto the retort is delayed until such time that the evolution of the residual content ofmoisture in the charge is completed and the charge has acquired a temperature of over 100 C. so that thus in no part of the period of distillation may the steam fallbelow the condensing point. In the use of cylindrical retorts, I prefer, however, to provide the retort of alarge size and so mounted as to be capable ofperiodic or continuous rotation as for. example once in four minutes.

Such a retort is described in thespecificanon of the co-pending application aforesaid dated the 20th January, 1919." In the use of'such retort, the application of heat tothe charge and-the distribution of steam therethrough at a temperature within the range herembefore' specified is rendered uniform and by distillation under these con ditions'l have secured higher yields of the distillation products than when the station-.

ary retort of the first modification isemplo ed.

From the foregoing it will be understood that by admitting steam within the range of temperature indicated a relatively high yield of the distillation products is secured and that with a view still further to 'im-, prove the yield where using a cylindrical retort it is preferable to cause its rotation for the purposesdescribed. By such means the total yield of the distillation products is increased.

Inlthe use :of the cylindrical retort whether stationary or rotary I prefer to provide a centrally disposed and perforated outlet pipe which when" the retort is arranged to retate permits of the movement of'the char e in the retort in the mannerdescribed in t e specification of the co-pending application aforesaid dated the 20th January, 1919.

' I claim:

1'. A method of increasing the yield of acetic acid, wood naphtha, or other distillati'on products in the destructive distillation of wood, woody' fiber and similar carbonaceous substances, consisting in subjecting the charge to distillation at a gradually increasing temperature by the uniform external application of heat to the retort within which the distillation is effected, and admitting steam into the retort at a substantially constant and relativel low temperature during the active period of distillation, substantially as described.

2. A. method of increasing the yield of acetic acid Wood naphtha, or other distillation products in the destructive distillation of wood, Woody fiber and similar carbonaceous substances consisting in subjecting the charge to distillation at a gradually increas: ing temperature by the'external application of heat to the retort Within. which the distillation is efi ected; and admitting steam into the retort at a substantially constant temperature between from about 180 C. to

about 270 C, during the active period of distillation, substantially as described 3. A; method of increasing the yield of acetic acid Wood naphtha or other distillation productsin the destructive distillation of Wood, Woody fiber and similar carbonaceous substances, consisting in, applying heat externally to the retort to effect the distillation and in the admission steam into the retort at a temperature be about 180 (l to about 270 C. i l poses and substantially as described,

4c. A method of increasing the yield of acetic acid, wood naphtha or other distillamenial tion products in the destructive distillation of Wood, Woody fiber and similar carbon'aceous substances consisting in applying heat externally to the retort to effect the distillation and in the admission of steam into the 'retort at a temperature between from about acetic acid,- wood naphtha or other distillation products in the destructive distillation ,of Wood, Woody fiber and similar carbonaceous substances, consisting in applying heat externally to the retort to effect the distillation and in the admission of steam into the retort at a temperature between. from about 180 C. to about 270 Q, for a period extend ing over the time during which the exothermic reaction takes place, substantially as described,

Perms PQORE. 

